Privilege Escalation in FOSSBilling (CVE-2026-53645)
Summary
Vulnerability in FOSSBilling (CVE-2026-53645). Risk of unauthorized operations or information disclosure. Exploitable via staff.create_and_edit_staff.
Original description
The description as published by the source.
FOSSBilling is a free, open-source billing and client management system. Versions prior to 0.8.0 allow a low-privileged staff account to grant arbitrary module permissions to itself through the admin API, resulting in persistent privilege escalation. A staff user that only has staff.create_and_edit_staff can call /api/admin/staff/permissions_update targeting their own account and write any permission structure, bypassing the intended role-based access control boundary. Version 0.8.0 patches the issue. Some workarounds are available. Restrict the staff.create_and_edit_staff permission to only highly trusted staff members and/or use a reverse proxy or WAF to restrict access to /api/admin/staff/permissions_update to specific trusted roles.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-53645 has been found in FOSSBilling.
Attackers can target a specific entry point like staff.create_and_edit_staff over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "FOSSBilling CVE-2026-53645" on the vendor's site.
CVE-2026-53645 (FOSSBilling) — CWE-269
Attack surface: staff.create_and_edit_staff
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-269) exists in FOSSBilling. Attackers reach the vulnerable code path via staff.create_and_edit_staff.
Check the vendor advisory for the affected versions of FOSSBilling. Attack surface: staff.create_and_edit_staff.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'FOSSBilling' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'FOSSBilling' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
FOSSBillingを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- advisory github.com
- advisory github.com
- advisory nvd.nist.gov